A user researching on a specific subject may ordinarily find many articles and references with conflicting or differing information. Often, it is important to determine the version number or publication date of an article in order to understand the value of the material and for example to know whether it is current or obsolete. Discrepancies in similar reference materials can be caused by outdated documentation or outdated versions that have been replaced or refuted by newer findings, for example, in the areas of scientific discoveries, medical studies, textbooks, or versions of programs and software packages.
It is not always easy or even possible to determine the origination date of a piece of information if it has been posted and re-posted numerous times, for example, by people in social networks, by news commentators or historical information sources. This issue may be especially prevalent in academic papers and many technology blogs.
While cached Internet search results may produce a date, a timestamp of a cached web document does not necessarily correlate to when the document was created. For example, the timestamp might have been updated long after the initial publication, or a user might have posted an old document on a new website which generated an artificially new cache timestamp.